worn clutch bushings

[Bill14viper]

installing a clutch kit on my 14 rtx and found bushings on the moveable shivs on both clutchs badley worn only 3000 miles completely stock. has anyone else seen this?

 

[titanrcr]

Not unheard of on the 4 stroke Yamahas, they seem to be a little harder on bushings. I Have done them at 3000-3500 mi due to excessive slop. The Secondary seems to take more of a beating. Should be done if you want good performance out of your clutches. You will need a grunt tool to pull the spider out of the primary and a press to do all the bushings. Average guy should send them out to someone that knows what their doing.

 

[Bill14viper]

so the spider is screwed on? i did not see a lock nut or threads like the polaris.

 

[cannondale27]

It is a sloppy fit new. Is the shaft scored? If not I bet the bushing are not out of spec.

 

[Bill14viper]

With the spring removed i can rock the moveable about 1/2 in on both clutches. Just seems loose. rpms very inconsistant. max rpm vary from 8300 to 9000 rpm thought the clutches may be binding.

 

[cannondale27]

That sounds normal at outer edge. If you look at the bushing you would see wear. I believe there are specs. Are you running stock clutching and 8jp?

 

[Bill14viper]

just installed the drag n fly kit not enough snow to really test it but it seems to have corrected hitting the rev limiter on launch. and thr 8jp but may try the gates belt.

 

[titanrcr]

With the spring removed i can rock the moveable about 1/2 in on both clutches. Just seems loose. rpms very inconsistant. max rpm vary from 8300 to 9000 rpm thought the clutches may be binding.

That sounds like a good amount of play, I'd be changing it for sure. A simple test is to pull the helix and spring, clean the shaft and the I/D of the bushing on the sliding sheave, Place the secondary flat on your bench, hold the inner face down with one hand and pull up on one edge of the sliding face with the other. The sliding half should should freely slide up the shaft. If you have too much play in that bushing it won't. When I do that bushing I change the helix bushing as well.

 

[titanrcr]

so the spider is screwed on? i did not see a lock nut or threads like the polaris.

The spider and shaft are screwed into the inner fixed sheave. Need a " grunt tool" which is a special holding fixture to disassemble the primary for service and gain access to the shaft bushing and plastic slider bushings in the outer half. At 4500-5000 mi. I do a full service on both clutches, they might seem to work just fine but performance will be off.

 

[Bill14viper]

Thanks for the info. I do have the tools as i have serviced my own clutches for years. This my first yamaha since 1988 exciter and have ridden polaris since then. I really do love the viper with the exception of the clutching. Very inconsitant right from the start. I think once its worked out it should be a great sled!

 

[titanrcr]

Thanks for the info. I do have the tools as i have serviced my own clutches for years. This my first yamaha since 1988 exciter and have ridden polaris since then. I really do love the viper with the exception of the clutching. Very inconsitant right from the start. I think once its worked out it should be a great sled!

Oh Man, I had an 87 Exciter, world of difference from back then to now. The new clutches are better now as well. Just read around this forum a bit and you will find tons of issues with stock clutch calibration and some guys running different belts on your viper. Good luck...

 

[stingray719]

If you ran an 8JP did you see a lot of black dust? That dust gets in the bushings and binds up the bushings that causes a lot of wear. Our first Viper at less than 50 miles had enough dust in the bushings that I had to clean them (and go to 8DN belt)

 

[Bill14viper]

Very little dust with the 8jp. changed out the original belt at 3000 miles just because but showed no wear at all. was still 1/16 above the secondary. Biggest problem has been hitting the rev limiter at launch and inconsistant wot rpm. hopefully the clutch kit helps.

 

[stingray719]

Very little dust with the 8jp. changed out the original belt at 3000 miles just because but showed no wear at all. was still 1/16 above the secondary. Biggest problem has been hitting the rev limiter at launch and inconsistant wot rpm. hopefully the clutch kit helps.

Hitting the rev limiter at launch is the 8GL weights, look at the profile and you will see a bump at the base that deliberately causes higher rpm at take off. Yes I know why put that weight in a torque 4 stroke.......

RPM hunting at WOT is the large rollers/weak spring combo, that is helped by 8DN belt and fixed with primary spring change.

Please let us know how the dragonfly weights work.

 

[cannondale27]

I would also like to see measurements or at least pics of the worn bushings. Just finding it hard to believe.